Troponin



Troponin (Tn) is a regulatory protein in muscle contraction. It contains 3 subunits: TnC causes conformational change in TnI when it binds to calcium ions. TnT binds to tropomyosin and TnI binds to actin which is found in thin muscle filaments. The images at the left and at the right correspond to one representative Tn, i.e. the crystal structure of complex Troponin C/Troponin I/Troponin T (1yv0).

3D Structures of Troponin
Update June 2011

Troponin C+Troponin I+Troponin T
2w49, 2w4u – cTnC+cTnI+cTnT+tropomyosin+actin – chicken

1ytz - cTnC+cTnI+cTnT+Ca++

1yv0 - cTnC+cTnI+cTnT

1j1d, 1j1e – hTnC (mutant)+hTnI (mutant) fragment+hTnT fragment+Ca++ - human

Troponin C+Troponin I
2krd – hTnC+hTnI – NMR

1ozs - hTnC C-terminal+hTnI N-terminal – NMR

2l1r - hTnC C-terminal+hTnI switch region - NMR

1lxf, 1mxl - hTnC N-terminal+hTnI fragment

2kgb – hTnC (mutant) regulatory domain+TnI

1sbj – cTnC C-terminal+cTnI N-terminal+Mg++ - NMR

1scv, 1fi5, 1blq - cTnC C-terminal+cTnI N-terminal – NMR

1npq - cTnC (mutant) N-terminal+cTnI fragment+rhodamine

1jc2 - cTnC C-terminal+cTnI N-terminal

1a2x - rTnC +rTnI fragment – rabbit

Troponin C
2kdh – hTnC+green tea polyphenol – NMR

2kfx – hTnC (mutant) N-terminal+Ca+naphthalene derivative

2jt0, 2jtz, 2jt8, 2jt3 – hTnC (mutant) – NMR

2jxl - hTnC (mutant) N-terminal – NMR

1wrk, 1wrl - hTnC (mutant) N-terminal+trifluoperazine

1spy - hTnC N-terminal– NMR

1ih0 - hTnC C-terminal+EMD 57033 – NMR

1ap4 - hTnC N-terminal+Ca++ – NMR

2l98 – hTnC EF-hand domains 3,4 + resveratrol

1la0, 4tnc – cTnC+Ca++

1dtl – cTnC (mutant)+Ca++ +bepridil

1skt, 1zac, 2ctn - cTnC N-terminal – NMR

1aj4 - cTnC (mutant) +Ca++ – NMR

3ctn - cTnC C-terminal – NMR

1avs - cTnC N-terminal+Ca++

1smg, 1tnq - cTnC N-terminal+Ca++ - NMR

1ncy – cTnC+Mn++

1ncx, 1ncz, 1top – cTnC

1pon, 1cta, 1ctd – cTnC fragment – NMR

1tnp - cTnC N-terminal – NMR

1tnw, 1tnx - cTnC +Ca++ - NMR

1trf - tTnC N-terminal+Ca++ - turkey – NMR

5tnc - tTnC

2k2a - TnC C-terminal – Lethocerus indicus – NMR

2jnf – TnC – fly – NMR

1r2u, 1r6p - TnC N-terminal – trout – NMR

1tcf – rTnC+Ca++

1tn4, 2tn4 – rTnC (mutant)+Ca++

Troponin I
2jpw – TnI biphosphorylated – mouse – NMR

1vdi – cTnI – NMR

1vdj – cTnI+Ca++ - NMR

Troponin T
2z5h – yTnT fragment+tropomyosin – yeast